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Terrestrial Planet Finder
solarlux writes "The Terrestrial Planet Finder has taken one step closer to reality as two architectures have been approved by NASA. The first, TPF-c, will be a single optical telescope which employs a coronograph to block starlight for planet detection. TPF-i will be a flotilla of infrared telescopes flying in formation to form a interferometer. TPF-i will analyze the planets identified by TPF-c for life signatures. The telescopes are to be launched within the next 10-15 years."
(looks down at the ground) Found one!
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
By then SETI might have actually found something. Remember, it intelligent life isn't dependent on a planet. Any advanced race probably left their world eons ago.
BLING BLING. Meet the architecture that's changing everything.
to find another planet. 150,000,000 years to get to it. Don't forget that we are seeing things as they used to be! discovering other planets is only has good as our ability to get there, which is nil. Not to mention that they probably arn't even there anymore.
I've always been very impressed by the timetables NASA is using. /me tips my hat to them
It must be an enormous task to plan so many years ahead into the uncertain future, not sure if the funding will be there.
This is the sig that says NI (again)
Once these things start piling up spectra. We could get some great surprises. Anyone wonder how things are going to change if they find a planet with a big chuck of oxygen in the atmosphere. Yet more proof that we're not quite so special :).
This is a great idea. I only hope the funding would be there to ensure launch of those telescopes. And that it won't be used as an argument against human exploration of space.
IMHO - something planned to happen 10-15 years from now has a great risk of not happening.
Entirely too much can change. You're talking about a funded project that would have to survive multiple shakes up in Administration (and think of all the Bureaucratic structures a NASA funded project relies on!!!) , not to mention a project that would have to be able to keep it's funding for that long.
Plus - in 10-15 years, it's entirely possible that technology might make this particular project irrelevant.
I don't get it. How is finding planets a good thing for the corps. and not the people?
This project just reeks of something orchestrated to generate popular interest in space exploration again. If we can identify a terrestrial planet, then just maybe people will want to go there, and NASA can get more funding, and the world will unite under one waving banner, and everyone will hold hands and sing "kumbaya"... Why not some more realistic goals/projects? I'm all for the spirit of exploration, but until someone can see profit from space travel, nothing will ever come from it (thank you, capitalism).
I think ultimately the question is whether there is a single continuous "initial mass function" of isolated objects or not. The best idea as to how stars acquire their initial mass is that turbulence in the interstellar medium, which exists on all scales, establishes a power-law distribution of initial masses. Every once in a while, you get a very strong shock which passes by inside a giant molecular cloud and forces the collapse of a large region which then goes on to form a massive star. But more typically, you form stars more like our sun. And just as rare as massive collapses are very small mass ones which go on to form isolated brown dwarfs and free-floating planets. If this model holds up to be true, then we are all mincing words in our definitions of isolated systems, since they are all manifestations of the same universal formation process.
However, to avoid the difficult question of formation mechanisms, an IAU working group of some of the most respected people in the field established a working definition to define by fiat what it means to be a brown dwarf, and a planet. Extrasolar "planets" are those objects orbiting a star which are beneath the deteurium-burning limit -- regardless of how they are formed. "Brown dwarfs" are defined to be those which burn deuterium but not lithium, and "sub-brown dwarfs" (NOT free-floating planets!) are defined to be those isolated objects which do not burn deuterium. Even the working group itself admitted that this definition was not satisfying to a single member of the group, and so it is likely it will be replaced at a later time with something more physically-motivated. The "planet/planetismal/KBO" distinction was pushed back to our own solar system, since it will be some time before anyone sees anything that small in another system.
Also of interest is the following link, which gives a history of previous claims for additional planetary members of our solar system : SEDS.
I've heard of the inferometry plan before - it's basically a fleet of 7 - 11 satellites flying in near-perfect line abreast formation. That coupled with a lot of image processing gives the effect of a radio telescope with a dish the size of the formation. There's some loss of resolution, but it's a massively cheaper way of doing it.
If they can get the formation steady that is.
'Don't worry' said the trees when they saw the axe coming, 'The handle is one of us.'
Check out the ESO's Overwhelmingly Large Telescope .. 100 meter diameter .. resolution of 1 milliarcsecond .. should be able to image the Lunar Lander on the moon when it's built.
http://www.eso.org/projects/owl/
-Johan
As usual, we are impared by our own lack of intelligence. We are going to spend a considerable amount of money building a complex infrastructure to retreive information that is... well... pretty much useless.
We'll be searching for a planet similar to Earth because we believe all life must come in some kind of carbon-made structure forming an organism that needs water to sustain itself and that releases some kind of carbon substance into the atmosphere. We also believe that life on Earth was possible to to it's "moderate" conditions. YET, we keep discovering ON EARTH new species previously unknown who live in the most extreme conditions.
So, from my point of view as an engineer... we'll be looking at a science subject without knowing exactly what to look for and without being able to extract any conclusive information. Futhermore, the technology that has to be developed to attain this study is not altogether new. So, no new relevant or important data, no new significant tech... What's the point, then?
If they need a sugestion on where to spend a couple of billion dollars... why not that not yet fully explored planet Earth, with loads of life that considers itself intelligent?
A few years back I (and I'm sure others have done the same) imagined an array of telescopes orbiting the sun in each of the Earth's Lagrangian points synchronized with extremely precise atomic clocks. Wouldn't a 2 AU array allow far better resolution?
I hate Grammar Nazi's
Related to this, as the BBC mentions here.
i don't like style guides
Could someone explain the difference between interferometry on the ground and in space? I thought that it was used to filter out atmospheric interference in ground-based telescopes?
:-)
Is space based interferometry used to filter out things like dust cloud and gravity distortion?
The thought of a huge solar system sized array of telescopes is most excellent
----- Documentation is worth it just to be able to answer all your mail with 'RTFM' - Alan Cox.
I'm curious... the article mentions that TPF-i will be a corroborative effort with the ESA. ESA, however, has been planning a similar endeavor named Darwin, which was to be a flotilla of eight infrared telescopes. So is the ESA folding their Darwin effort into TPF-i? If so, what will be the final name? If they settle on "Darwin", I imagine there might be an outcry by the American fundamentalist camp.
will ET find us before we find them?
they also will be looking for life signs and said their orbitals will be ready in 10-15 planetary cycles. and the asteroid launcher is looking promising, but won't be ready for another 70 planetary cycles, nor will it be able to reach speeds to make it worth waiting for, but its a great stealth attack.
Hasn't any moderator noticed?
I am somewhat involved with the European version of these missions (the Darwin mission, to be launched around 2014), so I might clear some things up.
Goal: to detect earth-like planets around other starts. Extra-solar planets detected thus far are usually 'hot Jupiters': big planets that orbit the star in a few days. These are relatively easy to detect. Detecting an earth-like planet (which have not been found yet) is far more difficult. It is usually compared to detecting the light of a firefly (reflection of the planet) flying very close to a lighthouse (the star). Measurements need to be done in the far infrared because there the ratio between the planet and the starlight is the highest (but still only 1:10^6 !!). With some luck they might find traces of ozone and CO2 in the spectrum that might be an indication for life.
Methods:
-Coronography: Simply put it is just a conventional big (~10 meter) telescope with a shadow mask that blocks the light of the star. The light of the planet should get past the mask on the detector.
-Interferometry: Somewhat similar to the techniques used in radio astronomy. The resolution of a telescope improves by increasing its size. The trick is to combine several small telescopes. The resolution should then be comparable to the resolution of one big telescope that is as wide as the separation between the small ones. With radio interferometry you can do the 'beam combination' by computer. In optics however you have to physically combine the beams of the different telescopes. This requires flying satellites in formation with stabilities on the order of nanometers!! Current schemes are limited to several hundred meters. There are also some attemps to do this on earth.
There is quite a lot of politics going on between NASA and ESA at the moment about how they should cooperate. First ideas where to do an interferometry mission together, but now NASA has decided to go for coronography and postpone interferometry to 2020. ESA is sticking to interferometry.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
Somebodys got to build it. Which means plenty of opportunity for cost overruns, bloated budgets and just plain old engineering welfare programs. Inevitably, the first one will wind up landing in the ocean due to a metric-english snafu so we'll have to have a couple spares on hand.
And finding a planet will mean what to me? Cheaper energy resources? A more secure, peaceful environment?
Perhaps a qualified presidential candidate?
It's not an earth size planet - but this is prettty cool. BBC News - link "The historic first image of a planet circling another star may have been taken by the Hubble Space Telescope."
As someone said - "xenobiologists are good at designing experiments to look for xenobiologists". Who says you need terrestrial planets for life?
i hope that out of the labs and off the desks of the engineers working to design these incredible telescopes also comes new technology that's good for us average joes back here on good ol' earth. they brought us tang... who knows what's next?!
-T
Getting better at interstellar visualization brings back memories of playing Masters of Orion. Is it all coming true now?!
Now we need to get rolling on the impulsion stuff once we got the visuals going...
But if you have a self-sustaining colony in space, why even go to a planet? The difference between 66 days and 660 years is that after a few dozen generations, the inhabitants will probably either forget their original mission or chalk it up to "some old religion." Orson Scott Card addressed this "generation ship" issue in more detail in How to Write Science Fiction and Fantasy.
Maybe we'll find the planet that the Mexican UFO's are from!
Maybe we DID take the blue pill. You wouldn't remember anyway.
to find another planet. 150,000,000 years to get to it. Don't forget that we are seeing things as they used to be! discovering other planets is only has good as our ability to get there, which is nil. Not to mention that they probably arn't even there anymore.
You do realize that with a detection range of a few dozen to a few hundred light-years, we'll be seeing planets as they were at most a few dozen to a few hundred years ago, not hundreds of millions of years, right?
A laser boosted sail-probe could reach a nearby star system ( 10 LY) within one human lifetime. It would be impractial to send one big enough to carry humans, but an automated flyby survey would definitely be feasible.
the X prize has done spectacular things in 1/10 of the time and 1/1000 of the budget of NASA; why not offer lucrative (by petty civilian standards; peanuts to NASA) prizes for getting a working telescope of such-and-such specs into space as part of an array?
I am one of many. My idea is not unique, nor do I expect my voice alone to sway you. I speak in a chorus of opinion.
thanks for that Zork link.. ahhh, the memories...
I have something in common with Stephen Hawking...
Spacecrafyt that travel at a speed just below c are called time dilation craft, and though I understand the theory behind them, a theoretical method of generating thrust at such rates eludes me. If I were to write a story about the crew of a time dilation craft, how would I handle explaining the craft's propulsion and radiation shielding?
NASA's single most important goal is that of inspiring the next generation of scientists, engineers, and explorers. I believe that TPF will certainly achieve this goal, should it find other planets like earth (life or not!)
When I saw this image a few years ago on APOD, I was awestruck... I'd seen star maps before, but not one that included Sol. It was amazing, because suddenly the sky was no longer an infinitely far away billboard of beautiful sites... it was a place just like any other (albeit a bit difficult to get to). On the map you can see the closest stars are really so close compared to everything else... makes me think we might send interstellar probes in my lifetime.
I believe that if TPF succedes, the next generation will think of other stars the same way they think of the Sun... as places where worlds are.
For that reason alone, I hope TPF is the tremendous success it seems it could be!
Anonymous Divinity
--- To each of us a Truth is given.
since Mars hasn't proved all that exciting
'scuse me? Within the last 3 months Mars Express resp. the MERs have found on Mars:
a) water ice in the south polar cap, previously thought to be dry ice only;
b) traces of methane (!) in the atmosphere;
c) conclusive evidence for a standing body of liquid water in the past.
All of which is raising the possibility of at least microbial life on Mars, fossil and/or present, which I find plenty exciting. I know it's not much by the entertainment standards of the MTV generation, but what did you expect - little green men taking us to their leader?
I for one find it remarkable that documents such as the Mars Express status report now routinely refer to "biological processes" as candidate explanation for observations without batting as much as an eyelash. And Mars Express hasn't even commenced its official science mission yet! Plenty to look forward to.
Be faithful to your obsessions. Identify them and be faithful to them, let them guide you like a sleepwalker. JG Ballard
Score one for a Robert L. Forward fan. Not the best in plot and character development but nifty science.
Underloved Movies and Pub Quiz: donotquestionme.org
Score one for a Robert L. Forward fan. Not the best in plot and character development but nifty science.
I actually doubt that the Forward scheme for sail decelleration will be used. The problem is that you need an array with an aperture size large enough to hit the primary sail at destination range, instead of just 1 LY or so (distance at the end of the boost phase). This makes it a lot more expensive to build.
You also end up having to use a truly huge primary sail (so that it can focus on the secondary sail at about 1 LY range at the end of the decelleration phase), and keep it perfectly aligned optically during decelleration.
A maser-driven craft with an active-antenna mesh that could do phase-shifting as the primary sail might be able to do this, but primary sail size and maser array size become prohibitive.
Fast-flyby probes are much easier to construct and boost, so I think they're more likely to be implemented if a sail scheme is used at all.
Nope.